A shop had 800 novels. There were English, Malay and Chinese novels in the ratio of 1 : 4 : 5. When the shop assistant brought in another 256 new novels, the number of English novels was increased by 20% and the number of Malay novels was increased by ¹₂.

1. What was the number of Chinese novels that the shop assistant brought in?
2. What was the percentage increase in the number of Chinese novels?

	English	Malay	Chinese	Total
Before	1 u	4 u	5 u	800
Change	+ 0.2 u	+ 2 u	+ ?	+ 256
After	1.2 u	6 u	6 u	1056

Increase in the number of English novels
= 20% x 1 u
= ²⁰₁₀₀ x 1 u
= 0.2 u

Increase in the number of Malay novels
= ¹₂ x 4 u
= 2 u

Total number of novels at first
= 1 u + 4 u + 5 u
= 10 u

10 u = 800

1 u = 800 ÷ 10 = 80

Increase in the number of English and Malay novels
= 0.2 u + 2 u
= 2.2 u
= 2.2 x 80
= 176

Number of Chinese novels brought in
= 256 - 176
= 80 

(b)
Number of Chinese novels at first
= 5 u
= 5 x 80
= 400

Percentage increase in Chinese novels
= ⁸⁰₄₀₀ x 100%
= 20%

Answer(s): (a) 80; (b) 20%